This invention relates generally to an electronic residential electricity meter.
Typically, electrical power supplied for residential applications is single phase alternating current power. To measure the consumption of electricity in residential applications, a meter is provided at the electrical service entrance to the residence. There are generally three types of meters for residences: (1) electromechanical based meters; (2) electronic meters; and (3) hybrid electromechanical/electronic meters. The electromechanical and hybrid type meters are essentially an induction motor in which the moving element is a rotating disk. The speed of rotation of the disk is directly proportional to the voltage applied and the amount of current flowing through the motor. The phase displacement of the current, as well as the magnitude of the current, is automatically taken into account by the meter i.e., the power factor influences the speed of rotation of the disk. The result is that the disk rotates with a speed proportional to true power. In the electromechanical type of meters, a register is used to register the number of revolutions, and the gearing is arranged to be read directly in kilowatt-hours.
Electronic meters are more complex and as a result tend to be more expensive. In particular, electronic meters use multiple circuit boards, current sensors, and voltage sensors.